Printed circuit board and method for manufacturing same

Abstract

A printed circuit board includes an insulating layer, a copper layer formed on the insulating layer and a reinforcing layer formed on the copper layer at opposite sides of the given portion. The copper layer includes a plurality of electrical traces at a given portion thereof. A thickness of the reinforcing layer increases in a direction away from the given portion. A method for manufacturing the printed circuit board is also provided in this disclosure.

1. A method for manufacturing a printed circuit board, comprising:
 providing a copper clad laminate (CCL), the CCL including an insulating layer and a copper layer formed thereon, the copper layer including a central portion and a peripheral portion surrounding the central portion; 
 forming electrical traces in the central portion; and 
 forming a reinforcing layer on the peripheral portion at opposite sides of the central portion, a thickness of the reinforcing layer increasing in a direction from the center of the CCL to a periphery thereof. 
 
     
     
       2. The method as claimed in  claim 1 , further comprising removing the reinforcing layer, the peripheral portion of the copper layer and a portion of the insulating layer corresponding to the peripheral portion of the copper layer. 
     
     
       3. The method as claimed in  claim 1 , wherein the reinforcing layer is formed using an electro-less plating process, or an electro-plating process. 
     
     
       4. The method as claimed in  claim 1 , wherein the reinforcing layer is formed using a method comprising:
 forming a metal layer on the peripheral portion using an electro-less plating process, or an electro-plating process; and 
 etching the metal layer to obtain the reinforcing layer. 
 
     
     
       5. The method as claimed in  claim 1 , wherein the reinforcing layer is formed using a method comprising:
 forming a metal layer on the peripheral portion using an electro-less plating process, or an electro-plating process; and 
 grinding the metal layer to obtain the reinforcing layer. 
 
     
     
       6. A printed circuit hoard, comprising:
 an insulating layer; 
 a copper layer formed on the insulating layer, the copper layer comprising a given portion, a peripheral portion surrounding the given portion, and a plurality of electrical traces at the given portion; and 
 a reinforcing layer formed on the peripheral portion of the copper layer at opposite sides of the given portion, a thickness of the reinforcing layer increasing in a direction away from the given portion. 
 
     
     
       7. The printed circuit board as claimed in  claim 6 , wherein the thickness of the reinforcing layer linearly increases in the direction away from the given portion. 
     
     
       8. The printed circuit board as claimed in  claim 6 , wherein the reinforcing layer includes a plurality of stacked layers, the stacked layers comprising an innermost layer directly formed on the copper layer and an outmost layer, a width of the layers decreasing in a direction from the innermost layer to the outmost layer. 
     
     
       9. The printed circuit board as claimed in  claim 8 , wherein the stacked layers are aligned with each other. 
     
     
       10. The printed circuit board as claimed in  claim 6 , wherein the reinforcing layer comprises a first portion and a second portion spaced apart from the first portion, the first portion formed on one side of the given portion and the second portion formed on another side of the given portion opposite to the one side. 
     
     
       11. A flexible printed circuit board, comprising:
 an insulating layer; 
 an elongated copper layer formed on the insulating layer, the copper layer comprising a central portion, a peripheral portion surrounding the central portion, and a plurality of electrical traces at the central portion; and 
 a reinforcing layer formed on the peripheral portion of the copper layer at opposite sides of the central portion, a thickness of the reinforcing layer gradually increasing in a direction away from the central portion, the direction being substantially parallel with a lengthwise direction of the copper layer. 
 
     
     
       12. The flexible printed circuit board as claimed in  claim 11 , wherein the reinforcing layer comprises a first portion and a second portion spaced apart from the first portion, the first portion formed on one side of the central portion and the second portion formed on another side of the central portion opposite to the one side.